TW595112B - Digital/Analog converter for LCD and method thereof - Google Patents

Abstract

A digital/analog converter is disclosed, which is for converting the digital pixel data into the corresponding Gamma voltage signal. The D/A converter at least comprises: a pixel data converting unit to output the corresponding conversion pixel data based on the digital pixel data. The correspondence relationship between the digital pixel data and conversion pixel data is determined by the color of pixel display. The Gamma correction unit is coupled to the pixel data conversion unit to output the corresponding Gamma voltage signal based on the conversion pixel data. The correspondence relationship between the conversion pixel data and Gamma voltage signal is determined by the sampling Gamma voltage signal inputted into the D/A converter.

Description

595112

[Field of the Invention] The present invention relates to a digital analog conversion device and method, and more particularly, to a digital analog conversion device and method for a liquid crystal display. [Background of the Invention] Since the liquid crystal display (Liquid Crystal Display, LCD) The advantages of thin volume, light weight and low electromagnetic radiation have become more and more widely used in recent years. For a liquid crystal display, since the cross-voltage and light transmittance between the upper and lower plates are not linear, when the digital pixel data to be displayed is converted into a voltage signal input to both sides of the liquid crystal, Gamma correction must be performed to reduce the color distortion of the LCD monitor. Please refer to FIG. 1, which shows the relationship between the cross voltage of the upper and lower panels of the liquid crystal panel and the light transmittance of the liquid crystal molecules. In Fig. 1, the horizontal frame 4 represents the magnitude of the lower panel voltage when the upper panel voltage of the liquid crystal panel is ycom, and the vertical axis represents the light transmittance τ of the liquid crystal molecules. The driving circuit of the liquid crystal display is to change the light transmittance of the liquid crystal molecules in the daylight element by changing the cross voltage of the upper and lower plates of each pixel (pi xe 1) on the liquid crystal panel, so that the daylight element has different brightness. When the upper panel voltage of the liquid crystal panel is Vc0m, the difference between the lower panel voltage and Vc0m represents the magnitude of the cross voltage on both sides of the liquid crystal panel. As mentioned above, the cross-voltages of the upper and lower panels of the liquid crystal panel and the light transmittance of the liquid crystal molecules between the two panels are not linear, but the relationship of the Gamma curve shown in Figure 1. So when the upper board voltage is fixed at Vcom, the lower board voltage is called the Gamma voltage. In addition, the light transmittance of a liquid crystal is related to the magnitude of the cross-voltage supplied to both sides of the liquid crystal, and has nothing to do with the polarity of the voltage supplied to both sides of the liquid crystal. Therefore, the liquid crystal surface

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The relationship between the trans-voltage between the upper and lower plates and the light transmittance of the liquid crystal is a gamma curve symmetrical to the left and right sides with Vc0m as the center. Therefore, two Gamma voltages of the same size but different polarities are respectively input, for example, the positive polarity Gamma voltage Va and the negative polarity Gamma voltage Vb, and the light transmittance TO of the liquid crystal molecules of the day element is the same. In other words, suppose that there are two days when the voltage on the plate is Vcom ′ but the voltage on the plate is one pixel. , And the voltage of the other panel is

Vb ′ Although the panel voltages under these two pixels are different, the brightness displayed by the two pixels will be the same. For a liquid crystal panel, if the voltage of the same polarity is continuously supplied to each pixel, the liquid crystal molecules of the pixel will be damaged. Therefore, the liquid crystal molecules can be protected by interactively changing the polarity of the cross-voltage across the upper and lower plates. In other words, when a pixel needs to continuously display a fixed brightness, the lower plate of the day element can be controlled to have two voltages of different magnitudes interactively, so that the polarities of the cross voltages of the upper and lower plates are changed alternately. In this way, the liquid crystal molecules of the pixel will not be damaged due to the continuous display of a fixed brightness. Figure 2 of Mingshen Zhidi ’s diagram is a block diagram of a non-linear digital-to-analog converter (DAC) 2 0 2. The driving circuit of the liquid crystal display has a non-linear digital analog conversion unit 202 for converting the digital daylight data DATA into a corresponding Gamma voltage signal OUT according to the input digital data DATA and a plurality of specific gamma voltages GMV. Please refer to Figure 3, which shows a Gamma correction curve. The horizontal coordinate is the digital pixel data DATA value of a day prime, and the vertical coordinate is the Gamma voltage signal corresponding to the digital book pixel data DATA. The digital daytime data data is a binary signal of one six bits. In Figure 3, the Gamma curve includes positive

TW0513 (040128) CRF.ptc Page 6 595112 Correction No. f 90126466 V. Description of the invention (3) Gamma curve 402 with polarity and Gamma curve 404 with negative polarity. Among them, the positive-polarity gamma curve 402 and the negative-polarity gamma curve 401 are divided into five specific points A ′, B ′, C ′, D, and e, and A, B, c, d, and E. Input the Gamma voltage signals corresponding to these specific points ", n, v2, V3, and V4 ': and V9, V8, V7, V6, and V5 into the non-linear digital analog conversion unit 202's non-linear digital analog The conversion unit 202 can obtain the Gamma voltage signals corresponding to all the digital textbook data DATA by interpolation according to the Gamma correction curve in Fig. 3. Please refer to Fig. 4, which shows the non-linear digital analog conversion. The circuit diagram of the unit Gamma voltage signal generating circuit. The non-linear digital analog unit has a Ga Long a voltage signal generating circuit. The circuit is composed of two resistor strings. Among them, each resistor string system includes 255 resistors, respectively labeled R0, R1 ... R254. Input specific Gamma voltage signals V0 ~ V9 at the specific end points of the two resistor strings respectively. By appropriately setting the resistance value of each resistor in the resistor string, according to the law of voltage division, Gamma voltage signals corresponding to all the digital pixel data DATA are output at the nodes of the two resistor strings in the interpolation circuit. Please refer to FIG. 5, which shows a pixel p (N, shown on the LCD panel). Figure. In pixel P (N, M), the scanning line and data line ratios are orthogonal to each other. The motion of pixel P (N, M) is controlled by the thin-film transistor T (N, M). The gate of the thin film transistor T (N, M) is connected to the scanning line SN, and the source is connected to the data line%. As mentioned above, when the scanning line SN is enabled, the thin film The transistor t (n, M) will be turned on. At this time, the Gamma voltage signal is transmitted to the thin-film transistor τ (N, M) through the data line ^ to control the upper and lower plates of the day element P (N, M). Lightning across the board

TW0513 (040128) CRF.ptc 595112 --- Case No. Qfi〗 Deng 466_year month day Article change_ V. Description of the invention (4) Small. In this way, the pixel p (N, the unacceptable degree of display can be controlled by the gamma voltage signal. In a color liquid crystal display, each display unit is composed of three daylight elements. Among them, each daylight element It can display one of the three primary colors of red, green and blue respectively. The driving circuit of the liquid crystal display enters the gamma voltage k number obtained after gamma correction into the corresponding day pixels. By controlling the three pixels of each display unit The displayed brightness causes the display unit to display an appropriate color. Please refer to FIG. 6 'when the pixels shown are red, blue, and green, respectively, the Gamma voltage of the liquid crystal panel and the light transmittance of the liquid crystal molecules The relationship diagram of τ. In Figure 6, the three curves labeled R, G, and B respectively represent the corresponding relationship between the trans-voltage of the upper and lower plates and the light transmittance of the liquid crystal molecules when the pixels display red, green, and blue colors. As can be seen from Figure 6, the Gamma function curves of different colors are not the same. In addition, when the daylight displays red, blue, and green, respectively, the Gamma voltage that maximizes the light transmittance of the daylight liquid crystal molecules is different. VRM, VBM to VGM 'The order of the voltage value is: VBM < VGM < VRM. When the traditional non-linear digital analog converter performs Gamma correction, it is set to make the light transmittance of the liquid crystal molecules reach The large Gamma voltage VBM is the maximum value of the Gamma voltage signal output by the non-linear digital analog conversion unit. After that, the Gamma voltage Vbm is used as a reference to determine the different Gamma voltage signals corresponding to the digital daylight data. 'When the value of the digital data DATA is larger, the Gamma voltage signal corresponding to the (^ _3 correction is also increased accordingly. On the contrary, the brightness displayed by the controlled pixel is also brighter. Above Determining the Pair of Digital Pixel Data and Gamma Voltage Signal

595112 The correction number is 901%. Fifth, the description of the invention. (5) The way of the relationship # 士, &1; the shortcomings of 疋: when the book Xin Xiangan d & from, when: cold, the pixel penetration Zhe Yiban, Cha 5 丨 said: "Dan Jingying is not red or green," "β-you half", the law reached the attack. In this way, the media will be added with ν *. The panel display shows that the surface and the surface of the display are in good condition. [Objective and Summary of the Invention] There is a clock here. When the digital analog conversion of this display shows different colors, the crystal panel displays the daytime display according to the purpose of the present invention to transfer the digital pixel data to the digital pixel data. Department degree. The digital analog conversion device performs conversion of pixel data by performing pixel data conversion. The corresponding relationship is determined by the Gamma voltage signal < The above-mentioned digital analogy method, the method includes at least the corresponding conversion of the corresponding day-to-day data. The purpose of converting the pixel data to the month is to provide a liquid crystal display device and method, which can It has the best performance in its brightness. And increase the brightness of the liquid surface. A digital analog conversion device is proposed, which is replaced by a corresponding Gamma voltage signal. It is used to control the lighting of the corresponding celestial element on the display. At least includes the celestial element data conversion unit, and the color of the digital pixel data and the converted celestial element data is displayed in the step of 'corresponding to the output according to the digital pixel data'. Decide. The Gamma correction unit is connected to the output of the pixel data according to the conversion. Among them, the conversion daylight data and Gamma voltage are input to the digital analog conversion sampling device. The Gamma electrical conversion device performs the following steps for pixel data conversion: First, To convert digital pixel data into pixel data. Among them, the digital daylight data and conversion are determined by the color of the daylight display. After that, it will correspond to the Gamma voltage signal. Among them, turn

IHI

Page 9 595112 Amendment Emperor 9012R Resembles V. Description of the invention (6) The correspondence between the pixel data and the Gamma voltage signal is determined by a plurality of sampled Gamma voltage signals. In this way, the pixels that display red, monitor colors, and green can reach the maximum transmission rate, and the display screen can present the best development quality. In order to make the above-mentioned objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is exemplified below and described in detail with reference to the accompanying drawings. [Preferred Embodiment] The spirit of the present invention is that: when digital and analog conversion is performed on pixel data, the color displayed by the pixel inputted by the daylight data is taken into consideration to determine the corresponding digital daylight data. Convert pixel data. In other words, digital analog data conversion operations for inputting leucograms displaying red, pixels displaying blue, and celestial displaying green are individually performed. In this way, the red, blue and green pixels can reach the maximum penetration rate, so that the display screen can show the best image quality. Embodiment 1 Please refer to FIG. 7, which shows a circuit block diagram of the digital analog conversion device 702 proposed in this embodiment. The digital analog conversion device 7 02 is set in the driving circuit of the liquid crystal display to replace the function of the traditional non-linear digital analog conversion unit and convert the digital pixel data]) ATA into the corresponding Gamma voltage signal υττ output. Among them, the digital analog conversion device 702 is coupled by a pixel data conversion unit 704 and a Gamnia correction unit 706. The digital analog converter shown in Figure 7 is shown

IH Page 10 595112 ___ Case No. 90126466_year month_g_ amendment V. Description of the invention (7) Set 7 0 2 to execute the first flowchart of the method for converting celestial data. The first day-to-day data conversion method provided by the present invention includes at least the following steps: First, step 802 is performed to input digital pixel data DATA into a digital analog conversion device 702. After that, step 804 is executed, and the pixel data conversion step is performed. The celestial data conversion unit 704 converts the digital celestial data DATA into a corresponding converted celestial data TD. Among them, the corresponding relationship between the digital pixel data DATA and the converted day pixel data TD is determined by the pixels input by the digital pixel data DATA, and the display colors are determined. In other words, the same digital daylight data DATA obtained after the pixel data conversion step 804 converts the daylight data TD will vary with the color of the input pixel display. Please refer to FIG. 9, which shows the relationship between the Gamma voltage of the liquid crystal panel and the light transmittance T of the liquid crystal molecules when the pixels display red, blue, and green colors, respectively. As mentioned above, when the pixels display red, blue, and green, respectively, the Gamma voltages VRM, VM, and VGM that maximize the light transmittance of the liquid crystal molecules are as follows: vBM < VGM < VRM. In the present invention, when Gamma correction is performed, the maximum value of the Gamma voltage signal OUT corresponding to the digital pixel data DATA is: when the pixel displays red, the Gamma voltage VRM that maximizes the light transmittance of the liquid crystal molecules. After that, the Gamma voltage VRM is used as a reference to determine the Gamma voltage signal OUT corresponding to different digital daylight data DATA. The present invention converts the digital pixel data DATA into the corresponding converted pixel data TD by using a pixel conversion mapping table (pixel mapping table) built in the pixel data conversion unit 704 in advance. Among them, the converted pixel data TD | and the digital day pixel data DATA are binary data of six bits. As described above, the present invention separately applies a function for inputting a pixel for displaying red and a pixel for displaying blue.

I1H TW0513 (04012a) CRF.ptc Page 11 595112 _Case No. 9Q126466__ Month and Day Amendment V. Description of the invention (8) Day pixel and digital pixel data DATA showing green pixels Individually perform day pixel data conversion step 8 0 4. Therefore, the Gamma voltage signals ουτ corresponding to the digital data DATA for displaying different colors are not the same. However, it is necessary to follow the rule that the larger the digital data DATA value is, the larger the corresponding Gamma voltage signal out will be. The Gamma voltage signal OUT corresponding to the digital digital pixel data DATA used to display the red color is consistent with the above rules. Therefore, when the pixel data conversion step 804 is performed, it is not necessary to convert the digital daylight data used to display red "to perform the daylight data conversion. But for the digital pixel data DATA used to display blue or green, Lu 'When the Gamma voltage signal OUT corresponding to the maximum value of the digital daytime data DATA is the Gamma voltage VRM, please refer to FIG. 9. The larger the value of the digital data DATA, the corresponding the Gamma voltage signal OUT may be. Therefore, the day pixel data conversion unit 704 needs to perform pixel data conversion step 804 on the digital pixel data DATA for displaying blue or green. The pixel data conversion method proposed by the present invention is: · When When the maximum value of the digital daylight data DATA is 25 and the corresponding gamma voltage signal OUT is the Gamma voltage VRM, it is assumed that when the daylight green is displayed, when the grayscale value of the digital pixel data DATA is 240 pixels, it has the highest penetration. Transparency. In other words, the Gamma voltage signal corresponding to the digital pixel data DATA is VGM. When the digital daylight data DATA inputting green daylight data is input to the daylight data conversion step 804, The digital daytime data DATA of the grayscale value 0 to 25 5 is converted into the converted pixel data TD of the grayscale value 0 to 2 40. The corresponding method is: digits of adjacent grayscale values with weak discrimination of the human eye The pixel data DATA corresponds to the transformed day pixel data TD to the same gray level value. Because the brightness of the day pixel is nearly full

TW0513 (040128) CRF.pt Page 12 595112 ----- f ife 90126466 __ ±-said · _ 5. In the description of the invention (9), the human eye has weak discrimination of brightness. For example: suppose that the grayscale value of the pixel brightness is a maximum of 2 55. When the grayscale values of the pixel brightness are 2 5 5 and 254, the human eye can hardly discern the difference in brightness between the two. Therefore, for the digital daylight data DATA for displaying green, in order to comply with the rule that the digital data DATa value is larger, the corresponding Gamma voltage signal will increase accordingly. When performing the daylight data conversion step 8 04, pixels The corresponding relationship between the digital pixel data DATA and the converted pixel data TD set in the conversion correspondence table is: the adjacent digital pixel data DATA for high brightness is mapped to the same converted pixel data TD. For example, the high-brightness digital daytime data j) ATa with grayscale values 2 5 5 and 2 54 are converted into the converted pixel data TD with grayscale values 24 0. The principle and method of performing the astronomical data conversion step 804 on the digital astronomical data DATA for displaying blue are the same as described above, and are not repeated here. In this way, the maximum brightness can be displayed when the daylight displays red, green, and blue without affecting the picture quality of the display daylight. The brightness performance of pixels will be better than the traditional method. After performing step 804, proceed to step 806, the gamma correction step. The converted daylight data TD is input into the Gamma correction unit 706. The Gamma correction unit 70 6 is a digital analog converter (Digita_tc) __ AnalQg Converter (DAC), which is used to convert the converted pixel data TD into a corresponding Gamma voltage signal OUT. The conversion method is the same as the conventional practice, and will not be repeated here. In this way, the digital analog conversion device 702 can individually perform gamma correction on the digital daylight data DATA for displaying red, blue, and green, respectively. Finally, step 8 08 is executed to output the Gamma voltage signal OUT. ...

TW0513 (040128) CRF.ptc Page 13 595112-Case No. 90126466 _ year month day __ amendment _ V. Description of the invention (10) For the second embodiment, please refer to Fig. 10, which is shown as Fig. 7 The flowchart of the first analog data conversion method of the digital analog conversion device 7 0 2 in the figure. The second celestial data conversion method provided by the present invention includes at least the following steps: First, step 1 02 is performed, and the digital celestial data DATA is input to a digital analog conversion device 702. After that, step 104 is executed to determine whether the digital daily data DATA needs to be dynamically converted. In this embodiment, the pixel data conversion step is divided into a static conversion step 1006 and a dynamic conversion step 1 008, which are briefly described as follows: For the pixels of a liquid crystal display, when the brightness of the pixels is When changing, due to the physical properties of the day liquid crystal molecules, a response time is required. The longer the response time required for a pixel to change its brightness, the slower the response velocity of the pixel becomes. The traditional method of accelerating the response speed of pixels is: when the pixels change from low brightness to high brightness, in the next display frame (frame), first input a Gamma voltage that is higher than the original Gamma voltage signal out. No. OUT. By inputting a Gamma voltage signal OUT '' that is higher than the original requirement, the cross-voltage value between the upper board and the lower board can be pulled up faster to speed up the response speed of the pixels. The above method is called overdrive (overdrive). The present invention can cooperate with the overdrive method, and by appropriately selecting the output Gamma voltage signal OUT, the pixel brightness can be improved while the response speed of the pixel is also accelerated. At this time, the day pixel data conversion unit 7〇 2 is based on the Gammaf letter $ 0UT 'of the pixel input in the digital picture data DATA in the previous frame to determine the number of pixels when the pixel data is converted. Page 14 595112

_ Case No. 90126466 V. Description of the invention (11) The converted pixel data corresponding to the bit pixel data DATA is referred to as a moving step 1 0 0 8 (or a static step 1 0 0 6). When performing step 104, the pixel data conversion unit 704 compares the digital daylight data DATA used to input a certain pixel with the digital picture of the same pixel entered during the previous > check.素 信息 DATA ,. If the gray scale values of the digital book element 'data DATA and the digital pixel data DATA' are the same, perform the & static ^ conversion step 1 0 06; otherwise, perform the dynamic conversion step 1 0 08. When performing the static conversion step 1 0 06, the digital day pixel data]) a τ a and the converted pixel data TD are determined by the digital pixel data "by the rounded book element and its displayed color. The principle and method of operation are exactly the same as the day-to-day data conversion step 80 4 described in the second embodiment, which is not repeated here. The digital day-to-day data DATA performs a static conversion step 1 0 6 according to a pre-built correspondence table to obtain Convert pixel data TD. 'When performing the dynamic conversion step 1 0 08, the pixel data conversion unit 7 0 will first compare the input digital pixel data DATA with the previous output digital pixel data DATA, if the number is When the pixel data DATA is smaller than the previous digit and the pixel data DATA is too large, the pixel data conversion unit 704 will first generate a grayscale value based on the pre-built correspondence table. J A The digital pixel data DATA also requires large dynamic digital pixel data. After that, the dynamic digital day pixel data W is output to the Gamma correction unit 706 to generate a gamma voltage signal OUT. In this way, when the pixel is changed from low brightness At high brightness, y uses the overdrive method to speed up the response of day pixels. It should be noted that the corresponding relationship between 'dynamic digital day pixel data Dd and digital pixel data' and the previous digital pixel data DATA will also It varies depending on the color of the daylight that is input. Digital daytime data ^ based on pre-built

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The corresponding table performs the dynamic conversion step 1 0 8 to obtain the converted daylight data td. Next, step 101 is performed, a gamma correction step. After the converted book material data TD is input to the Gamma correction unit 706, the Gamma correction unit ^ performs the Gamma correction operation to convert the converted day-to-day data TD to the corresponding Gannna voltage signal OUT. The conversion method is the same as the conventional practice, and will not be described here. Finally, step 1012 is executed to output the Gamma voltage signal out. The present invention resets the maximum value of the G a m m a voltage signal output by the digital analog conversion device 702 when performing the gamma correction. The digital daylight data DATA for inputting pixels that display red, pixels that display blue, and pixels that display green are individually subjected to gamma correction. In this way, without affecting the daytime quality of the display screen, red, blue, and green daylight elements can display their maximum brightness. Compared with the conventional method, the present invention increases the maximum brightness that can be displayed when the pixels are displayed in green by 5%, and the maximum brightness that can be displayed when it is displayed in red is increased by 12%. As for the sensitivity to the human eye, the present invention can improve the overall brightness of the daytime display of the liquid crystal display by 10% to 20%. In addition, the present invention can cooperate with the implementation of the overdrive method when the brightness of the book display changes. This can speed up the response speed of daylight to change the brightness and reduce its response time. [Effects of the Invention] A digital analog conversion device and method for a liquid crystal display disclosed in the above embodiments of the present invention can make the pixels of the liquid crystal panel have the best performance when displaying different colors. And increase the brightness of the whole daytime surface when the LCD panel displays the picture. At the same time, when the brightness of the daylight is changed from low brightness to south tolerance, it can cooperate with the implementation of the overdrive method to speed up the response speed of pixel changes in brightness and reduce its response time.

TW0513 (040128) CRF.ptc Page 16 595112 _Case No. 90126466 _ Year Month Day _ ^ _ V. Description of the invention (13) In summary, although the present invention has been disclosed as above with a preferred embodiment, it is not To limit the present invention, anyone skilled in the art can make various modifications and retouching without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be defined by the scope of the attached patent Quasi

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Brief description of the drawing [Simplified description of the drawing] Fig. 1 shows the relationship between the light transmittance of the handle on the liquid crystal surface. Reverse the board's cross-voltage and liquid crystal partition. Figure 2 shows the non-linear digits. Figure 3 shows a Ga called positive curve change ... block diagram. Number "shows a non-linear digital analogy

Circuit diagram of Gamma voltage signal interpolation circuit. Figure 5 shows a schematic diagram of a conventional filfM compound-golden master \ dentin P (N, M) on a liquid crystal panel. Figure 6 and "1 show the relationship between the Ga? A voltage of the red, blue, and green plates and the light transmittance T of the liquid crystal molecules. Transfer: Device electricity Figure 8 shows a flowchart of the method for converting pixel data in the digital analog conversion device 702 shown in Figure 7. Figure 9 shows the liquid crystal when the pixels display red, blue, and green, respectively. The relationship between the Gamma voltage of the panel and the light transmittance τ of the liquid crystal molecules. Fig. 10 shows a flow chart of the second analog data conversion method of the digital analog conversion device 7 as shown in Fig. 7. [Fig. Explanation of equation labels] 2 0 2: Non-linear digital analog conversion unit 40 2: Gamma curve of positive polarity 4 0 4 · • Gamma curve of negative polarity

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Claims (1)

595112 _ Case No. Ml 26466 Che Yue Ri Zheng _ VI. Patent application scope 1 _ A digital analog conversion device for a liquid crystal display. The digital analog conversion device receives a digital pixel data and a plurality of sampling Gamma voltage signals, It is used to convert the digital pixel data into a corresponding Gamma voltage signal. The digital pixel data is used to control the brightness of a pixel. The digital analog conversion device includes at least: a pixel data conversion unit, Is used to output a corresponding one of the converted pixel data according to the digital pixel data, wherein the correspondence between the digital pixel data and the converted pixel data is determined by the color displayed by the pixel; and a gamma correction unit, Consumed with the pixel data conversion unit for outputting the Gamma voltage signal corresponding to the converted pixel data, wherein the correspondence between the converted day pixel data and the Gamma voltage signal is from the sampled Gamma voltage signals Decided. 2. The digital analog conversion device as described in item 1 of the scope of patent application, wherein the color displayed by the daylight element is one of red, blue, and green. 3. The digital analog conversion device described in item 2 of the scope of patent application, wherein a first Gamma voltage signal, a second Gamma voltage signal, and a third Gamma voltage signal can cause the pixel to display red and blue, respectively. And green have the maximum brightness, the maximum value of the Gamma voltage signal output by the pixel conversion device is the maximum value of the first Gamma voltage signal, the second Gamma voltage signal, and the third Gainffla voltage 彳 § Decide. 4. The & digital analog conversion device as described in item 1 of the scope of patent application, wherein the digital pixel data and the converted pixel data are all binary of N bits 595112 _Case No. 9Q126466__Year Month a Amendment 6. Range of Patent Application Bit data ’N is a positive integer. 5. The digital analog conversion device according to item 1 of the scope of patent application, wherein the digital analog conversion device is provided in a driving circuit of the liquid crystal display. 6. · A pixel data conversion method for a liquid crystal display, which is used to convert a digital day pixel data into a Gamma voltage signal, wherein the digital day pixel data is used to control the brightness of a pixel, the pixel The data conversion method includes at least the following steps: converting the digital pixel data into a corresponding one of the daylight data, wherein the correspondence between the digital pixel data and the converted pixel data is determined by the color displayed by the pixel And converting the converted day-to-day data into the corresponding Gamma voltage signal 'wherein' the correspondence between the converted pixel data and the Gamma voltage signal is determined by a plurality of sampled Gamma voltage signals. 7. The diurnal data conversion method as described in item 6 of the scope of patent application, wherein the color of the diurnal display is one of red, blue, and green. 8 · The daylight data conversion method described in item 7 of the scope of the patent application, wherein 'a first Gamma voltage signal, a second Gamma voltage signal, and a third Gamma voltage signal can cause the daylight to display red and blue, respectively. Color and green with maximum brightness, the maximum value of the Gamma voltage signal output by the pixel conversion device is determined by the maximum values of the first Gamma voltage signal, the second Gamma voltage signal, and the third Gainnia voltage signal . 9 · The pixel data conversion method described in item 6 of the scope of patent application, TW0513 (040128) CRF.ptc Page 21 595112 Case No. 90126466 said Amendment 1 The converted pixel data are all binary of N bits. F Patent application scope Among them, the digital pixel data is bit data, and N is a positive integer. 10. The pixel data conversion method as described in item 6 of the scope of patent application, wherein the day pixel data conversion method is performed by a driving circuit of the liquid crystal display. 11. A pixel data conversion method for a liquid crystal display, for converting digital pixel data into a gamma voltage signal, wherein the digital pixel data is used to control the brightness of a pixel, and the day pixel The method is used to display the color. The method of converting daytime data includes at least the following steps: a. Determine whether to perform dynamic conversion according to the digital pixel data and a previous digital pixel data, wherein the previous digital pixel data is a previous The digital pixel data used to control the degree of the day pixel 'if yes, execute step: if not, execute step b; b. Execute a static conversion step to convert the digital pixel data into the corresponding One of the statically converted pixel data, wherein the corresponding relationship between the digital pixel data and the statically converted daylight data is determined by the color displayed by the daylight pixel. After that, step d is performed; " c The conversion step converts the digital daylight data into a corresponding dynamic conversion daylight data, wherein the correspondence between the digital pixel data and ^ dynamically converted daylight data is determined by the pixel After the displayed color ^, the previous digital pixel data is determined, step d is performed; and d. The static conversion data, or the dynamically converted day pixel data is converted into a corresponding Gamma voltage signal, where the static Conversion of pixel cores and material and the corresponding relationship between the dynamic conversion data and the Gamma voltage signal ^ TW0513 (040128) CRF.ptc Page 22 595112 _Case No. 90126466_Year Month__ VI. The scope of patent application is determined by a plurality of sampling Gamma voltage signals. 1 2. The day-to-day data conversion method described in item 11 of the scope of the patent application, wherein the color displayed by the pixel is one of red, blue, and green. 1 3. The pixel data conversion method according to item 12 of the scope of patent application, wherein a first Gamma voltage signal, a second Gamma voltage signal, and a third Gamma voltage signal can cause the pixel to display red , Blue and green have maximum brightness, the maximum value of the Gamma voltage signal output by the daylight conversion device is the maximum value of the first Gamma voltage signal, the second Gamma voltage signal, and the third Gamma voltage signal The value is determined. 1 4. The method of converting day-to-day data as described in item 11 of the scope of the patent application, wherein the digital pixel data, the statically-converted pixel data, and the dynamically-converted day-to-day data are all N-bit binary data, N Is a positive integer. 1 5. The pixel data conversion method as described in item 11 of the scope of patent application, wherein the pixel data conversion method is performed by a driving circuit of the liquid crystal display. 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